The present invention relates to golf club putters and more particularly to golf club putters having an improved weight and "shaft-force-axis" distribution system.
The majority of golfers who play the game of golf produce erratic and inconsistent golf swings. The same is true for putting strokes which exhibit very little in the way of repeatable performance. This is caused by a variety of reasons, both physical and mental, resulting in a rather large percentage of putts which are not hit on the "sweet-spot" or percussion center of the putter head and thus travel off-line with respect to an intended path toward a target. Each time a ball is struck from a point other than the center of percussion, a turning moment or force is created which seeks to rotate or turn the putter head, thus influencing the ball to roll a direction other than the intended target direction, and with less energy or speed transferred to the ball than originally intended. Both of these results adversely effect the performance and scoreing potential of the golfer. The result effected by the turning force is a function of both the distance between the point of impact and the center of percussion, and the clubhead's effective polar moment of inertia. Thus, a golf club head with a larger effective polar moment of inertia will turn less for a given off-center hit of a given force than a golf club head with a small or effective polar moment of inertia for the same hit.
Many efforts have been made to improve the performance characteristics of golf clubs, particularly golf putters, by increasing the moment of inertia primarily by altering the weight distribution characteristics of the club head. The most wellknown of these type of putter club heads use heel-toe weighting which concentrates the weight of the club head near or at the heel and toe portions. This arrangement tends to provide offcenter hits of a golf ball which cause less turning of the club head than occurs from similar impacts with clubs which have essentially even mass distribution across the hitting face. There also have been efforts to provide weight distributions high and low relative to the striking face of the putter club head to impart various characteristics to the ball being struck on a putting surface. Various mallet type putters have been provided with hollow interiors including means for adding or removing weights to control weight distribution.
Related patent art includes U.S. Pat. No. 1,537,320 to Marsh which shows a golf club having a protuberance which is rearwardly projecting and substantially elongated and cylindrical which is formed integral with the club head. The protuberance facilitates aiming and tends to overcome faulty shots by locating some of the club head mass at a somewhat increased distance from the point on the face of the club head which should properly engage the ball and thus increasing the club head effective polar moment of inertia, and reducing its propensity to turn or rotate.